K1000 bass enhancement

I got a box from Germany on Saturday (thank you Jan). It contained one Corda amp (a thing of beauty) and an SAC amp for the K1000s (a beast).

I worked 16 hrs Saturday, so no time to play :-(

I started listening Sunday, but I only made it to the second song on the first Avenue Blue CD (highly recommended) when I remembered that the K1000s don't quite have that bottom octave. I normally don't miss it that much, but that song needs it. Since I can't get through a week without an audio experiment, that was all the reason that I needed.

They just need a subwoofer, right? It just so happens that I have a few of those laying around! I grabbed an old ADS PB1500 and it's electronic crossover and set it in the middle of the room (subwoofers and walls do not interact well, imho).

The results were too good. I wish that I hadn't tried this, because now I am hooked. Everything that the K1000s delivered before, with the bottom octave restored! Since I was close to the sub it didn't take much augmentation. As a bonus the mids cleaned up slightly, probably because the K1000 drivers were not moving much anymore. They normally have visible excursion when there is significant low frequency information.

I am already working on a compact bandpass sub design specifically for these phones. More experiments ahead!

I am just searching for the middle ground...
you know, somewhere between extreme and insane.

It wasn't obnoxious at all...

I set the phones down and walked into the next room, and could not even hear the sub, although I could hear the highs from the Ks. Since I was in nearfield, it took very little power to the sub to get serious deep bass. I wasn't driving the whole room into resonance.

I put the HD600s on after a couple of hours of listening to the K1000s with sub. Not a good jump to make. They were pretty pale in comparison, although they do have better bass than the K1000s alone.

I realize that this in an impractical arrangement, and I only tried it out of curiosity. Unfortunately I like the results and will now be on a quest to improve it.

you know, I think jude's been good about his upgrades for nearly two weeks now. not bad! One can only guess at what will be coming next, since all of his upgrading instincts are most likely going to explode in a flurry of tweaks and mods...

Originally posted by Nerudayou know, I think jude's been good about his upgrades for nearly two weeks now. not bad! One can only guess at what will be coming next, since all of his upgrading instincts are most likely going to explode in a flurry of tweaks and mods...

Actually, I came this close to ordering the Beyers again, but, once again, convinced myself not to. I'm going to try -- for the next couple/few weeks -- not to buy any new equipment, and instead buy music exclusively. I've already got tomorrow's music purchase planned (see music forum).

I tried this method about two years ago. Probably my subwoofer is crappy but the bass leak through headphone grills murkied sound. That's why when sensational shaker like Butt Kicker became popular, I was quite thrilled. Only found out that those devices still give off sound and degrade bass quality. Closed headphone like R10 may be a better match.

Jude, I understand your "struggle" as I'm on the shopping spree myself after acquiring Jude Syndrome.

A couple of tips...

Keep the crossover frequency low. Way below 100 hz. I like 50 to 60 for the K1000s, since they start rolling off at 50.

Steep slopes on both sides. I think that my ADS is only 12db/octave. I will try a 24 next.

Use a true active crossover, with both high-pass (to the phone amp) and low pass (to the sub amp). A lot of the powered cubes on the market now lack an active high-pass side. They typically have a passive first or second order for the "satelite" speakers.

Deep response! Something that is -0 db at 20hz anechoic would be ideal, but nearly impossible to find (but not to build).

tomcat, they were great headphones. For me they were a bit too bassy, but that's just my opinion. They're an amazing set of closed cans. I would imagine that they would sound less bassy depending on the fit (they fit me a bit too tightly, so the bass might have been increased). I can certainly see why you liked them. My only serious problem with them was that they didn't seem to get large enough for me. That might have effected what I was hearing, too.

Neruda,
I am just glad about any company in this Beyer 770/990 corner of mine. At times, it's getting a little lonely over here. And that you say that you prefer them to the Senn HD 600, as well...
Makes me seem less crazy.

Greg, (or anyone else)
i was wondering if you ever tried the following with sub-woofers with your K1000 headphone. i have very little experience with sub-woofers and none in using a sub with a K1000 or bi-wiring so i was hoping you might know if these ideas would work well.

i was thinking of hooking up my Cambridge Audio A500 Integrated amp. with an amplified sub using the left and right pre-amp out RCA's connected to the subs line IN's RCA connectors while the K1000 would remain connected to the speaker connectors. This set up seems like it would work well but the K1000 would still have to cover the full range of freqs down to levels where it may start to distort and disrupt mid-freqs as mine does now.

Or i was thinking i could try making use of the A500 bi-wiring capability by hooking up the sub to the bass freq speaker connector set while the K1000 is hooked up to the higher freq speaker connector set. this i presume would free up the K1000 of the bass freq load but the A500 manual gives no information at where the freq cut off point is between the high freq and bass freq connectors but the sub-woofer would have a freq cut off adjustment so maybe this won't matter.

Do these set ups sound workable? i like the 2nd set up better being that at it would presumeably give the K1000 only the lower mid to high feq loads where it does very well while the sub handles the bass down to 30 hz or lower.